The Balbina dam is operated by Eletronorte and was inaugurated in 1989. It came as part of a national integration and economic growth offensive (the Programa de Aceleração do Crescimento, PAC) that was pushed forward by Brazil’s military government in the 1960s and 1970s in the Northern Amazon. The start of dam constructions in 1979 followed the controversial construction of the BR-174 highway (see related case entry in the EJAtlas) that cut through dense rainforest and the land of the Waimiri Atroari community (self-denomination: Kinja), which had so far been living rather isolated and whose presence was seen as disturbing. At the point of dam construction, the Balbina area was inhabited by riverine communities along the Uatumã as well as the Waimiri Atroari indigenous group. However, the spread of diseases and extreme violence exerted by the military during road construction in the 1970s led to a drastic decline and the near distinction of the indigenous population, from an estimated 3,000 in the 1970s to 332 people in 1986. Moreover, the isolated Piurititi indigenous group has widely disappeared since then. In 1979 mining groups linked to the Paranapanema group started to invade nearby indigenous lands in which large cassiterite deposits were found. The military government controversially dissolved the demarcation of the indigenous land to regularize mining operations that continue until today (see also related case entry in the EJAtlas) and expropriated an area of 10,300 km2 for public utility, superimposing it to the territory of the Waimiri Atroari group. This permitted the eventual flooding of approximately 2,928 km2 through the Balbina project, including at least eight indigenous villages, leading to the displacement of about one third of the surviving indigenous population and about 3,000 riverine families downstream of the dam.         
Balbina was built with the objective to produce hydroelectricity for industries in nearby Manaus and mining operations, but turned out to be highly inefficient so that soon a second smaller dam was created in Pitinga to exclusively supply Paranapanema’s mining operations. Already at time of construction of Balbina various experts alerted about the absurdity of the Balbina dam but were ignored by the government. The dam was build in an almost flat area and therefore resulted in the flooding of a vast area while the power generated remained insignificantly low, covering only about 10 percent of the current demand of Manaus, and reaching not even half of its actual capacity of 250 MW due to low water levels of the Uatumã river.   
For comparison, Brazil’s giant dam in Tucuruí, Pará – constructed in the same period and flooding an almost identical area, thereby causing devastating social and environmental impacts – has an energy capacity of 8,370 MW. At the same time, following the privatization of the energy distribution system in Amazonas in 2018 – as Eletrobrás sold its distribution affairs to the Oliveira Energia Atem consortium – the Balbina plant has now also the highest electricity tariffs from all hydropower concessionaires in Brazil.
Nevertheless, the Balbina project came with tremendous socio-environmental impacts. Due to the flat topography, the flooding also created about 3,546 islands and fragmented wildlife habitats in which species became isolated and endangered. As a recent study pointed out, this has been the main factor for the decline in biodiversity, despite attempts to relocate animals before the inundation. The dam also disrupted migration cycles of fishes, leading to the decline of fishes and turtles in the Uatumã river, eliminating the main food source of the affected communities. The decline in fish species can also be explained through the high levels of putrefaction as before the inundation of the area only two percent of the primary forest vegetation was cleared. While decomposing plant matter led to high levels of methane emissions, the acidification rendered the use of water by the communities impossible and with that, illnesses and diseases augmented. Hence, displaced communities moved closer to the BR-174 where they were given food by the mining operator, which further reduced their capacity to maintain an independent living.  
Recent studies (e.g. Kemenes et al. 2011) have proven the significant methane and carbon dioxide emissions from the Balbina reservoir and argued that through the conversion of tropical forest – formerly a net sink for greenhouse gases – into a floodplain, tropical hydroelectric dams like Balbina became a significant factor for atmospheric warming.   Moreover, due to the minimal energy output of the Balbina dam, “the atmospheric emission factor of 2.9 tons of CO2 eq C/MWh of generated energy is several times higher than that of a coal-fired thermoelectric power plant (0.3 tons of C/Mwh).” 
Fearnside (1989) calls the building of the dam a ‘pyramid to folly’ and points out that it came along with a failure of the environmental impact assessment system and strong lobbying in the course of political decision-making in a context of high population growth and energy demand in Manaus and a series of questionable economic development projects in the Amazon. The dam would ultimately only serve the interests of construction companies and politicians who can demonstrate the creation of employment and commerce. Moreover the low-level waters of the reservoir were particularly attractive for mining companies. In fact, the creation of a flooded reservoir with low water levels facilitated cassiterite ore mining through floating dredges as these could access mineral occurrences in the upper reaches of the submergence area (depths less than 6m), making almost the entire Balbina reservoir accessible for surface mining.  
In addition to that, the dam project, together with related large-scale road construction and mining interventions as well as newly installed military outposts (as part of Brazil’s Calha Norte national security project) continuously increased pressure on the Kinja community throughout the 1980s. As Baines (2008) notes, the interventions had been accompanied by FUNAI’s civilization mission and an imposition of power structures since the 1970s, leading to the systematic incorporation of the Kinja community into the rationales of the colonizers, a subsequent loss of cultural identity and the capacity to live autonomously along with socio-cultural change and social divisions. The established ‘developmentalist’ logic also persisted after the end of military rule but became more and more disguised in a rhetoric of indigenous self-determination.  While this led to the successful reclaiming and demarcation of parts of the historical Waimiri Atroari land, it also introduced compensation logics as a means to legitimize the various interventions. Most notably, the Waimiri Atroari Program was initiated in 1987 and is since then financed by Eletronorte in an attempt to mitigate the damages caused by the dam. The program provided new livelihoods for displaced communities and led to improvements in areas such as health, education and environmental protection. Baines (2008) however concludes that the program represented an outside institution over which the community had no control and primarily served the interest to depict images of indigenous resistance and cultural revitalization to the wider public.    
Confronted with the new realities, the Kinja community has over the past decades held a number of protests in order to demand higher compensation payments from Eletronorte and Paranapanema – e.g. by blocking the access road to the Pitinga mine as well as the BR-174 highway (see related case entries for more details). Protests against the hydroelectric dam on the other hand have been articulated by the Movimento dos Atingidos por Barragens (MAB) and hundreds of affected families, who – 30 years after the dam opened – still continue to fight for the recognition of their rights. This includes in particular riverine communities formerly living downstream of the dam who have lost their homes with the flooding of the Uatumã river, and, with the collapse of fisheries, also their main source of food supply, leading to upstream migration and the occupation of abandoned provisional shacks in the Balbina village, originally built for the construction workers. Many of them were initially promised compensations or resettlement but continue living there informally and in poor conditions. 
In the last years, pressure on the local community in Balbina village – whose population is now of 2,300 – has increased due to the advancing privatization of Eletrobras and the regional distribution system, a legislative initiative that was pushed forward under the Temer government in 2018. Thus, villagers have become obliged to pay for electricity and prices have significantly augmented in recent years, while public services in the Balbina district, including schooling and health, are still controlled by Eletrobrás (Eletronorte) and are being affected by the privatization process. In addition to that, villagers also report the destruction of gardens and farming activities through Eletrobras representatives as the company does not permit subsistence practices in areas that are ‘designated for reforestation’.  Recent protests of the local MAB movement however successfully prevented the power cut-off of 192 families. Demonstrations continued in 2019 and were directed against further privatization and the closing of the local hospital, which would affect a total population of 8,500 people in the village and its surroundings.  
Most recently, communities in the area became confronted with new plans for an electrical transmission line through their territory (plans that have caused a wide political outcry, see also related conflict in the EJAtlas) and the Kinja group was threated by Eletronorte with the stop of funding for the Waimiri Atroari Program if they continued to reject the project.